This invention relates to a machine intended for automatically positioning and continuously feeding containers, for example bottles or other hollow articles made from synthetic material, which may be of very different sizes and shapes, with the ability to change its rate of production by units of time within very wide margins. This machine is designed for continuous feeding of other machines such as high production filling machines or similar equipment and is able to carry out this function owing to the large number of containers which it can position correctly and feed per unit of time.
Known machines of the type to which the present invention relates may include in general:
a) a hopper of any shape or dimension provided with an opening to receive in bulk containers that fall onto a bottom plane whose edges are at a distance from the side wall of the hopper providing a space allowing the passage of the containers;
b) a structure, provided with displacement means in enclosed circuit, located below the bottom plane, including, fully or in part:
a plurality of detachable container holding elements removable mounted at the periphery of the structure defining between their sides, the edge of the structure, and the hopper wall, a series of recesses adapted to receive containers in a lying position and provided with retaining means for one part of the containers, namely their neck, in such a way as to release them in a predetermined position, usually with the neck upward; PA0 a plurality of discharge chutes provided under the recesses for receiving and transferring the containers, correctly oriented, towards an exit conveyor that feeds, for example, a bottling line; PA0 Aidlin machine (U.S. Pat. No. 3,295,659) relates to a machine comprising a hopper into which the containers or bottles which are to be sorted are randomly loaded, having an inclined axis, an inclined disc constituting the bottom of the hopper and adapted to rotate about the inclined axis, a plurality of openings at the periphery of the disc each adapted to receive and pass one container while retaining the neck which is supported on the disc for transporting them from a receiving zone to an unloading zone, associated with a fixed plate beneath and parallel to the rotatable disc providing a support for the container bodies during their rotation and having a release opening in an upper part of the plate aligned with the path of movement of the containers as the disc rotates, so that the containers fall, by gravity, one by one in an upright position into a fixed chute or guideway located below the opening; PA0 Nalbach machine (U.S. Pat. No. 3,650,368 and U.S. Pat. No. 4,865,181) includes an inclined rotating annular surface provided, with a row of receiving areas for the bottles seated in a lying position, delimited by attached holding elements provided with retaining means for the neck of the bottle, the annular surface providing for carriage of the bottles from a lower loading area to an upper unloading area, and associated with a lateral fixed plane that provides a support for the bottles during their rotation and has, at the upper part an opening to pass the bottles that fall, by gravity, in an upright position into a chute located below the opening. PA0 NALBACH machine mentioned above includes a plurality of chutes mounted on a revolving drum below the bottom of the receptacle or hopper and of the retainer fixed plane associated with an intermediate fixed plane located in the passage of the chutes and designed to prevent the bottles from directly falling onto the exit conveyor; PA0 Aidlin machine above adapts to different shapes and dimensions of the containers by changing the rotatable disc provided with openings by means of screws located in the area of its axis; PA0 Schindel machine (U.S. Pat. No. 4,130,194) improves on Aidlin machine by only requiring changing the annular marginal part of the rotatable disc, provided with peripheral apertures to lodge the containers in a lying position, and evacuating the annular segments by the upper part of the receptacle; PA0 Marti machine (U.S. Pat. No. 4,681,209) which describes a container positioning machine having a plurality of chutes mounted on a revolving drum below the bottom of the hopper integral with a rotatable disc assembly, the recesses for receiving the containers in a lying position on the disc assembly being formed by detachable parts which are interchangeable with replacement parts to accommodate different shapes and sizes of containers being handled wherein the chutes are also removable and exchangeable with chutes of different sizes. PA0 Marti machine (U.S. Pat. No. 4,928,808) shows an unscrambler for unscrambling and orientating containers including a hopper having straight or slightly curved walls, a plurality of travelling carriages having holding elements with openings for receiving individual containers and passageways for receiving and positioning the containers, the travelling carriages moving along an enclosed path and being interconnected and drawn by a flexible or hinged drive belt, and an adjustable shelf disposed between holders and passageways for supporting the containers until they reach a discharge station where they drop through an opening in the shelf, the holding elements and passageways also being removable to accommodate different shapes and sizes of containers.
c) a plane or shelf, which may be adjustable in height, located below the recesses and over the chutes, designed to support the containers when they are conveyed by the holding elements defining the recesses for receiving and retaining them in a lying position, the plane or shelf being provided with an opening in an unloading area through which the containers drop when moved into position thereover by the container holding elements;
d) a means, e.g. air nozzle means for directing air jets for ejecting incorrectly positioned containers from the recesses towards the loading area in the hopper, e.g. bottles seated in an incorrect manner and/or protruding from the recesses;
e) air nozzle means provided in the unloading area for directing air jets which help tilt the containers correctly positioned in the recesses, toward discharge chutes;
f) air nozzle means designed to eject out of the hopper containers not discharged in the unloading area, e.g. those that are faulty.
Machines known to the applicant are the following grouped by the function they perform:
a) Automatic Container Erection
b) Automatic Aligning Of The Containers
c) Accommodation Of The Machine To Different Container Shapes
It is understandable that in a machine having these characteristics an important parameter is reliable operation on which total production directly depends, because of which some automatic machines are equipped with control and/or safety components designed to immediately detect any irregularity in the state of the containers (imperfect finish, irregular shape, etc.) or in their positioning in the container transfer means within the machine. Malpositioned containers are pushed back into the receiving or loading area by appropriate means such as nozzle means connected to a suitable compressed air source, as described in European Patent EP 85 106953.4. Nozzle means combined with a belt conveyor provided with appendages is described in the above-mentioned U.S. Pat. No. 4,928,808. When the bottles are defective, they should immediately be rejected and removed from the recesses just after having passed over the discharging zone as in the above-mentioned U.S. Pat. No. 4,681,209 by sensor means and blower means that effects the removal of defective containers to a gathering cavity situated adjacent to the side wall of the hopper, in such a way that they do not at any time interrupt the functioning of the machine.
These machines are not entirely suitable and effective for continuously feeding containers such as bottles at a high speed rate because of the exigencies under these circumstances for an intensive pressurized air jet, as well as for ejecting malpositioned or defective bottles from the transporting recesses, or for assisting the tilting of the container toward the falling chutes. Due to the inertia of the containers produced by high speed operation, zones arise where bottles adhere to the recesses and side wall of the hopper which can not be prevented only by common pressurized air devices. Thus expensive, sophisticated and particularly noisy equipment has been used.